I have been practicing Dentistry for over 30 years and have been using magnification for almost 25 years. I started with Designs for Vision, then Orascoptic, then Surgitel, then Sheer Vision and finally Snap on Optics. The changes were made due to weight, magnification and cost. Snap on Optics is able to deliver all 3 without compromising any of the things I feel are essential to good glasses. The quality of the product and the value you get cannot be beat. The owner, Ray, always accommodates my needs. His customer service is 5 stars. Thanks for the VIP treatment I always get from Snap on Optics.